Q: How are the tapered rollers of tapered roller bearings connected to the inner ring?
A: Single-row tapered roller bearings consist of an inner ring with a tapered raceway, an outer ring, tapered rollers, and a basket-shaped cage. They mainly bear radial and axial combined loads, mainly radial loads. Almost all tapered rollers use a basket-shaped cage stamped from low-carbon steel plates. Its structural shape is shown in the figure below. This cage has a simple structure, good strength, and is easy to process. It is currently a structure commonly used by bearing companies at home and abroad.
The tapered roller bearing with a basket-type cage is designed with a small non-working rib on the inner ring. Its function is to make the inner ring, roller and cage an inseparable assembly, so as to facilitate the assembly and installation of the bearing. However, due to the existence of a small rib on the inner ring, the basket-shaped cage manufactured according to the product drawing size cannot directly carry out the assembly process of the inner ring and roller of the bearing. For this reason, the basket-shaped cage must be expanded again after stamping and before the bearing is assembled, that is, the small end of the cage is enlarged a little, so that after the roller is installed in the cage pocket, the inner ring with the small rib can be smoothly installed. Then, the small end of the cage is compressed to a finished product size close to the product drawing using a special assembly mold. When assembling the bearing, the roller should be installed in the cage pocket first, and then the inner ring should be put in. The method of inserting tapered rollers into the cage pockets is usually done manually in medium and small batch production, and can be done by roller loading machinery or automated devices in large batch production. After the expanded cage is loaded with rollers and inner rings, it is compressed to a finished product size close to that specified in the product drawing using a special assembly mold. -Generally, the expansion process of the cage is carried out in the cage manufacturing workshop, while the compression process of the cage is carried out in the bearing assembly workshop after the rollers and inner rings are loaded. Therefore, using the assembly mold to compress the cage is the main task of the assembly workshop. The main function of the tapered roller bearing assembly mold is to compress and restore the expanded basket-shaped cage to the size and geometry specified in the product drawing to ensure the normal operation of the bearing and the rotation flexibility and noise requirements.
The expansion or contraction of the cage is completed by the press and the mold. Correct adjustment of the press and the optimized design of the mold can ensure that the inner ring, roller and cage of the tapered roller bearing are tightly combined. After the basket-shaped cage is contracted, the main assembly process of the tapered roller bearing is completed. After that, the bearings are demagnetized, cleaned, and inspected for internal components’ nominal width deviation, rotational flexibility, noise, and various vibrations. Qualified finished tapered roller bearings can then be installed on various equipment and used normally.
